ColdFire:Add mb for 5253 dram initialization

The dram initialization sequence should be in order.
This patch add mb for the dram intialization code to make
sure the compiler do not disorder the code.

Signed-off-by: Jason Jin <Jason.jin@freescale.com>

diff --git a/arch/m68k/include/asm/io.h b/arch/m68k/include/asm/io.h
index 531f420336cd447b6781f6a27ae3e9965c010e5c..d86eaf95eac8c84875b641a9e33f002eb2cbb53a 100644 (file)
--- a/arch/m68k/include/asm/io.h
+++ b/arch/m68k/include/asm/io.h
@@ -81,6 +81,8 @@
 #define outl(val, port)                out_le32((u32 *)((port)+_IO_BASE), (val))
 #endif
 
+#define mb() __asm__ __volatile__ ("" : : : "memory")
+
 extern inline void _insb(volatile u8 * port, void *buf, int ns)
 {
        u8 *data = (u8 *) buf;

diff --git a/board/freescale/m5253demo/m5253demo.c b/board/freescale/m5253demo/m5253demo.c
index 4772074d81fb94e55672804ecd2235c492f5b33d..8ffb2cc0447d9df58cf48523619f87af7687ef59 100644 (file)
--- a/board/freescale/m5253demo/m5253demo.c
+++ b/board/freescale/m5253demo/m5253demo.c
@@ -27,6 +27,7 @@
 #include <common.h>
 #include <asm/immap.h>
 #include <netdev.h>
+#include <asm/io.h>
 
 int checkboard(void)
 {
@@ -63,10 +64,12 @@ phys_size_t initdram(int board_type)
                __asm__("nop");
 
                mbar_writeLong(MCFSIM_DACR0, 0x0000322c);
+               mb();
                __asm__("nop");
 
                /* Write to this block to initiate precharge */
                *(u32 *) (CONFIG_SYS_SDRAM_BASE) = 0xa5a5a5a5;
+               mb();
                __asm__("nop");
 
                /* Set RE bit in DACR */
@@ -83,6 +86,7 @@ phys_size_t initdram(int board_type)
                __asm__("nop");
 
                *(u32 *) (CONFIG_SYS_SDRAM_BASE + 0x800) = 0xa5a5a5a5;
+               mb();
        }
 
        return dramsize;